As prior art car antennas for reception of different frequencies, there are arrangements disclosed in JP-U-60-10092B, JP-P-62-179202A and JP-P-62-245805A in which all rods forming each antenna are extended and retracted by a motor-driven system.
A problem of the prior art antennas is that a power feeding cable is caught in rods connected thereto during their retracting movements, and this often causes a malfunction. There are further drawbacks that the directivity and the gain are insufficient and that the structure is complicated and expensive.